1. Field of the Invention
The present invention generally relates to a dampening bracket for a vehicle roof panel. More specifically, the present invention relates to a vehicle roof structure with a dampening bracket that can prevent unpleasant noise from being generated in the passenger compartment from the sound caused by vibration of the roof panel of the passenger compartment.
2. Background Information
Passenger vehicles sometimes encounter a situation in which roof panel vibrates. In particular, the roof panel sometimes vibrates as a result of vibrations from vibration sources such as the engine and the like. If the resonance frequency of the roof panel from this vibration is that same as the cavity resonance frequency of the vehicle body, or is greater than this cavity resonance frequency, then the roof panel emits noise such that an unpleasant noise is generated inside the passenger compartment.
One example of a technique that has been proposed as a countermeasure for preventing the generation of an unpleasant noise in the passenger compartment as a result of the vibration of the roof panel is described in Japanese Unexamined Patent Application No. 59-29366. In this publication, a dampening steel plate is joined by bonding to the undersurface of the roof panel, which adds mass to the roof panel so that the resonance frequency of the roof panel is shifted from the cavity resonance frequency of the vehicle body. In such a construction, however, since a dampening steel plate is directly joined by bonding to the undersurface of the roof panel, which has a large vibration amplitude, there is a danger that this dampening steel plate will separate from the roof panel by this vibration, and may, in the worst case, fall from the roof panel.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved vehicle roof panel dampening bracket. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.